What type of cervical spine MRI (Magnetic Resonance Imaging) should be ordered for a patient presenting with a head tremor?

MRI for Head Tremor Evaluation

For patients with head tremor, an MRI of the brain without and with IV contrast is the most appropriate imaging study, as it provides optimal evaluation of brain structures involved in tremor pathophysiology while MRI of the cervical spine is not routinely indicated unless there are specific neurological signs suggesting cervical pathology.

Rationale for Brain MRI in Head Tremor

Head tremor typically originates from abnormalities in central nervous system structures rather than cervical spine pathology. The cerebello-thalamo-cortical network is particularly implicated in tremor disorders 1:

• Brain MRI allows visualization of key structures involved in tremor generation:

  • Cerebellum (particularly posterior lobe)
  • Thalamus
  • Cortical areas involved in motor control
  • Brainstem structures

• Research has demonstrated specific anatomical changes in brain areas controlling movement sequencing in tremor patients, including:

  • Atrophy in the left medial orbitofrontal cortex
  • Changes in the cingulate gyrus
  • Alterations in the paracentral lobule and lingual gyrus 1

Specific MRI Protocol Recommendations

Brain MRI Protocol

• T1-weighted sequences (pre and post-contrast)
• T2-weighted sequences
• FLAIR sequences
• Susceptibility-weighted imaging (SWI)
• Diffusion-weighted imaging (DWI)

These sequences allow comprehensive evaluation of structural abnormalities that may be associated with tremor. T2-weighted sequences are particularly valuable for identifying lesions in the thalamus and cerebellum 2.

When to Consider Cervical Spine MRI

Cervical spine MRI is generally not the first-line imaging study for isolated head tremor. According to the ACR Appropriateness Criteria, there is "no relevant literature regarding the use of MRI cervical and thoracic spine without IV contrast in the evaluation of isolated dizziness" or related movement disorders 3.

However, cervical spine MRI may be considered if:

• There are concurrent neurological signs suggesting cervical pathology
• The patient has symptoms of myelopathy
• There is a history of cervical trauma
• The patient has signs of cervical radiculopathy

Evidence Supporting Brain MRI

Research has demonstrated the utility of brain MRI in evaluating tremor disorders:

• Resting-state functional MRI studies have shown differences between patients with essential tremor with and without head tremor, with increased activity in the bilateral posterior lobe of cerebellum in patients with head tremor 4

• MRI has been established as superior to CT for detecting neurological abnormalities, with one study noting that "MRI should be the first step in detecting abnormalities of the brain and cervical spine" 5

• MRI can help differentiate between tremor subtypes by identifying specific patterns of abnormality:

  • Head tremor is associated with cerebello-cortical abnormalities
  • Arm tremor without head involvement shows more thalamo-cortical abnormalities 4

Clinical Approach to Imaging Selection

1. Begin with brain MRI without and with IV contrast for all patients with head tremor
2. Include specialized sequences to evaluate the cerebellum, brainstem, and thalamus
3. Consider cervical spine MRI only if there are specific signs or symptoms suggesting cervical pathology
4. For follow-up imaging (e.g., after treatment), T2-weighted and susceptibility-weighted sequences are most valuable 2

Common Pitfalls to Avoid

• Focusing only on the cervical spine when the pathology is likely intracranial
• Ordering cervical spine imaging without clear indications of cervical pathology
• Failing to include appropriate sequences to evaluate the cerebellum and thalamus
• Not considering functional MRI when structural MRI is normal but tremor persists

By following these recommendations, clinicians can optimize the diagnostic yield of neuroimaging in patients with head tremor while avoiding unnecessary studies.